Jung-Hyun Choi

Characterization of the left atrial vortex flow by two-dimensional transesophageal contrast echocardiography using particle image velocimetry.

This article is the first clinical investigation of the quantitative left atrial (LA) vortex flow by two-dimensional (2-D) transesophageal contrast echocardiography (2-D-TECE) using vector particle image velocimetry (PIV). The aims of this study were to assess the feasibility of LA vortex flow analysis and to characterize and quantify the LA vortex flow in controls and in patients with atrial fibrillation (AF). Thirty-five controls and 30 patients with AF underwent transesophageal contrast echocardiography. The velocity vector was estimated by particle image velocimetry. The morphology and pulsatility of the LA vortex flow were compared between the control and AF groups. In all patients, quantitative LA vortex flow analysis was feasible. In the control group, multiple, pulsatile, compact and elliptical-shaped vortices were seen in the periphery of the LA. These vortices were persistently maintained and vectors were directed toward the atrioventricular inflow. In the AF group, a large, merged, lower pulsatile and round-shaped vortex was observed in the center of the LA. In comparisons of vortex parameters, the relative strength was significantly lower in the AF group (1.624xa0±xa00.501 vs. 2.105xa0±xa00.226, pxa0<xa00.001). It is feasible to characterize and quantify the LA vortex flow by transesophageal contrast echocardiography in patients with AF, which offers a new method to obtain additional information on LA hemodynamics. The approach has the potential for early detection of the LA dysfunction and in decisions regarding treatment strategy and guiding anticoagulation treatment in patients with AF.

Interleukin-10 deficiency aggravates angiotensin II-induced cardiac remodeling in mice.

AIMSnThis study examined the role of interleukin (IL)-10 in angiotensin II-induced cardiac remodeling.nnnMAIN METHODSnAngiotensin II was infused subcutaneously (1.1mg/kg/day) for one week in IL-10 knockout and wild-type mice, after which cardiac function and hypertrophy were assessed by echocardiogram.nnnKEY FINDINGSnIL-10 gene expression in the heart was increased by angiotensin II infusion. Plasma levels of brain natriuretic peptide (BNP) and gene expression of BNP in the heart were increased by IL-10 deficiency or angiotensin II, and plasma BNP levels were further increased by IL-10 deficiency with angiotensin II. IL-10 deficiency increased the left ventricular dimension, whereas treatment with angiotensin II increased heart weight. Angiotensin II significantly reduced cardiac function in IL-10 knockout mice compared with wild-type mice. Gene expression of tumor necrosis factor-α and interleukin-6 was increased by IL-10 deficiency or angiotensin II infusion, and these increases were further enhanced by IL-10 deficiency with angiotensin II. Gene expression of collagen I/III and collagen III protein levels were increased by angiotensin II but not by IL-10 deficiency. Gene expression of matrix metalloproteinase2/9 was increased by IL-10 deficiency or angiotensin II, and this expression was further increased by IL-10 deficiency with angiotensin II. Akt phosphorylation was increased by IL-10 deficiency or angiotensin II and further increased by IL-10 deficiency with angiotensin II. Phosphorylation of p38 was increased by IL-10 deficiency.nnnSIGNIFICANCEnThese results suggest that IL-10 deficiency causes deterioration in cardiac functions in angiotensin II-infused mice, suggesting that IL-10 plays a protective role against angiotensin II-induced cardiac remodeling.

The Clinical Impact of Bedside Contrast Echocardiography in Intensive Care Settings: A Korean Multicenter Study

Background and Objectives We assessed the ability of portable echocardiography (with contrasts) to clearly delineate the cardiac structure, and evaluated the impact of its use on the diagnosis and management of critically ill patients in Korea. Subjects and Methods We prospectively enrolled 123 patients (mean age 66±16 years), who underwent portable transthoracic echocardiography (with contrast) for image enhancement at 12 medical centers. The quality of the global left ventricular (LV) images, the number of the regional LV segments visualized, the ability to visualize the LV apex and the right ventricle (RV), and any changes in the diagnostic procedure and treatment strategy were compared before and after the contrast. Results Of the 123 patients, 52 (42%) were using mechanical ventilators. The amount of poor or uninterpretable images decreased from 48% to 5% (p<0.001), after the contrast. Before the contrast, 15.6±1.1 of 16 LV segments were seen, which improved to 15.9±0.6 segments (p=0.001) after the contrast. The ability to visualize the LV apex increased from 47% to 94% (p<0.001), while the inability to clearly visualize the RV decreased from 46% to 19% (p<0.001). Changes in the diagnostic procedure (for example, not requiring other types of imaging studies) were observed in 18% of the patients, and the treatment plan (medication) was altered in 26% of patients after the contrast echocardiography. Conclusion The use of a contrast agent during the portable echocardiography, in intensive care settings, can improve the image quality and impact the diagnostic procedures and treatment for Korean patients.

Echocardiographic Assessment of Structural and Hemodynamic Changes in Hypertension-Related Pregnancy

Background Pregnancy induces dramatic cardiovascular changes in order to meet the increasing metabolic needs. Adaptive change of left ventricle (LV) might be modified in pregnancy complicated by hypertension. Methods Data from 193 consecutive pregnant women were analyzed. Clinical and echocardiographic data were compared in normotensive and hypertensive women. Results Significantly higher LV mass indexed by height was observed in hypertensive women compared with normotensive women (84 ± 21 g/m vs. 97 ± 20 g/m, p = 0.001). Diastolic function measured by the ratio of peak velocity of early diastolic transmitral blood flow to early diastolic mitral annular velocity was impaired in hypertensive women (11.0 ± 3.0 vs. 9.2 ± 2.5, p < 0.001). Such change was more prominent in women with gestational hypertension (GH) than those with chronic hypertension (CH). Heavy maternal weight was an independent factor associated with LV hypertrophy (LVH) in both normotensive and hypertensive women. Overt eccentric LVH was more frequent than concentric remodeling/hypertrophy (24% vs. 8.4%) in GH, while the opposite result was observed in CH (14% vs. 23%). Conclusion Hypertensive pregnancy is associated with significant LVH and diastolic dysfunction. CH seems to induce different LV remodeling pattern from GH. Heavy maternal weight during pregnancy might intensify the unfavorable remodeling of LV, particularly in hypertensive pregnancy.

Prediction of hemorrhagic transformation following embolic stroke in patients with prosthetic valve endocarditis.

Background Hemorrhagic transformation (HT) of stroke is a disastrous complication in patients with infective endocarditis (IE). In patients with mechanical heart valves complicated by IE, physicians struggle with the appropriateness of anticoagulation administration given the risk of thromboembolism and HT of stroke. In this study, we aimed to define predictive parameters of HT of stroke in patients with prosthetic valve endocarditis (PVE). Methods This study was a multicenter, retrospective design. We recruited from 7 institutions a total of 111 patients diagnosed with PVE during May, 2011 to April, 2012. Results Complication of stroke was seen in 26/111 patients (23%), and HT of stroke was seen in 11/111 patients (10%). Most patients with HT (9/11, 82%) had supratherapeutic prothrombin times. However, there were no significant differences in clinical and laboratory values between PVE patients without stroke and those patients who had a stroke and with or without concurrent HT. Furthermore, echocardiographic parameters also did not show significant between-group differences. Conclusion Even though this was a multicenter study, a limited number of patients was identified and may explain the negative results seen here. However, a large number of PVE patients with stroke also developed HT. Therefore, further studies to define predictive parameters of HT should be implemented in a larger population.

Impact of Contrast Echocardiography on Assessment of Ventricular Function and Clinical Diagnosis in Routine Clinical Echocardiography: Korean Multicenter Study

Background Fundamental echocardiography has some drawbacks in patients with difficult-to-image echocardiograms. The aim of this study is to evaluate impact of contrast echocardiography (CE) on ventricular function assessment and clinical diagnosis in routine clinical echocardiography. Methods Two hundred sixty patients were prospectively enrolled over 3 years in 12 medical centers in Korea. General image quality, the number of distinguishable segments, ability to assess regional wall motion, left ventricular (LV) apex and right ventricle (RV) visualization, LV ejection fraction, changes in diagnostic or treatment plan were documented after echocardiography with and without ultrasound contrast agent. Results Poor or uninterpretable general image was 31% before contrast use, and decreased to 2% (p<0.05) after contrast use. The average number of visualized LV segments was 9.53 before contrast use, and increased to 14.46 (p<0.001) after contrast use. The percentage of poor or not seen LV regional wall motion was decreased from 28.4% to 3.5% (p<0.001). The percentage of poor or not seen LV apex and RV was decreased from 49.4% to 2.4% (p<0.001), from 30.5% to 10.5% (p<0.001), respectively. Changes in diagnostic procedure and treatment plan after CE were 30% and 29.6%, respectively. Conclusion Compared to fundamental echocardiography, CE impacted LV function assessment and clinical decision making in Korean patients who undergo routine echocardiography.

Effects of contemporary management on clinical outcomes in elderly patients with acute myocardial infarction

acute myocardial infarction Jun-Hyok Oh , ChanghoonKim ,Mi Jin Yang , Sung Gyu An , HyeWon Lee , Jung-Hyun Choi , Han Cheol Lee , Kwang Soo Cha ⁎, Taek Jong Hong a and others from the Korea Acute Myocardial Infarction Registry a Department of Cardiology, Medical Research Institute, Pusan National University Hospital, Busan, South Korea b Department of Preventive Medicine, Medical Research Institute, Pusan National University Hospital, Busan, South Korea